The present invention relates generally to a composition and a method for weight loss, reduction of serum cholesterol, and normalization of insulin response without requiring added caloric restriction. More specifically, the present invention relates to combinations of psyllium and chitosan, in a proper ratio, which synergistically adsorb dietary fats and inhibit their gastrointestinal absorption.
In recent years, people have tended to become less physically active and consume food that has a high fat content. Such sedentary life styles and excessive lipid ingestion cause obesity and along with it a variety complications, for instance, heart and circulatory diseases, respiratory disease, diabetes and the like.
It is known that the fat content of foods is a major factor in the problem of obesity. It is also understood that the body tends to store fat for future use rather than utilize it immediately, which leads to weight-gain. Furthermore, it has been shown that there is a connection between the amount of fat stored in the body and the level of serum cholesterol, with a diet high in fat being likely to lead to high serum cholesterol levels. As cholesterol has been implicated as a factor in arteriosclerosis or hardening of the arteries, the risk for heart disease and/or a heart attack is increased when a diet high in fat is followed.
Therefore, a composition along with a safe and easy method of treatment, which facilitates a person""s effort to lose weight and to control the accumulation of harmful cholesterol, are needed and will be appreciated. Such a composition or method should preferably be capable of aiding a person in accomplishing these goals without requiring additional caloric restriction or interfering with the taste of food. Ideally, such a product or method, by preventing the body from absorbing the fat in such food once ingested, would permit a person to eat the foods they most like, while not unduly worrying about the amount of fats contained therein. Such a composition would aid the body in the rapid elimination of ingested fats prior to digestion in order to prevent the build-up or accumulation of harmful cholesterol.
It is known that dietary supplementation with psyllium, a water-soluble dietary fiber, can be effective in lowering cholesterol levels. In chemical terms, psyllium extract is a water-soluble mucilage consisting of a highly branched, acidic arabinoxylan. The decrease in cholesterol with psyllium supplementation can be affected with or without any additional dietary changes. See, for example, U.S. Pat. Nos. 6,048,532; 5,891,441; 5,258,181 and 5,173,296, which all are incorporated herein by reference.
Chitosan (FIG. 1A) is a natural, polymeric carbohydrate made through the deaceylation of chitin (FIG. 1B). Currently popular as a dietary supplement, chitosan is capable of binding fat, both triaceylgylcerols (TGs) as well as fatty acids. Based upon in vitro data, it has the potential to assist in weight loss and thereby reduce the incidence of obesity-associated conditions such as cardiovascular disease and type II or non-insulin dependent diabetes.
Chitin, the precursor to chitosan, was first discovered in mushrooms by the French researcher Henri Braconnot in 1811. In the 1920s chitin was also isolated from insects. Chitin is the most abundant natural fiber next to cellulose and is similar to cellulose in many respects. The primary source of chitin today is from the shells of shellfish such as crab and shrimp. The preparation of chitosan was described in 1859. It is made by cooking chitin in alkali, much like the process for making soaps. After alkali treatment, the links of the chitosan polymer are composed of repeating glucosamine units containing a free amino group. These amino groups take on a positive charge at pH values below their pKa. At pH values above the pKa, the molecule loses its charge and becomes neutral. This action sequence is important in the physiologic effects of chitosan in binding neutral, dietary triglycerides.
The ability of chitosan to bind fat has generated great interest in the molecule recently. Like some plant fibers, chitosan is not digestible and therefore has no caloric value. However, unlike neutral plant fibers, chitosan""s charged nature gives it the potential ability to bind significantly more fat than any plant fiber. Under physiologic conditions, chitosan can bind an average of four to five times its weight in fat, although in vitro studies demonstrate triglyceride binding of as much as 10 to 100 times its weight.
In recent years, it has been found that chitosan can be used as a dietary supplement for reducing lipid absorption in mammals. See, for example, U.S. Pat. Nos. 4,223,023; 5,453,282; 5,976,550; 5,932,561; 5,773,427 and 5,736,532, which are incorporated herein by reference. While the results of in vitro fat binding studies are impressive, it has not been previously disclosed that chitosan can be used for weight loss without subjecting the individual to a restricted calorie diet. Only laboratory animal studies support the weight loss properties of chitosan. Human clinical studies reported in scientific journals do, however, substantiate a significant reduction in serum LDL cholesterol with the use of chitosan. A significant improvement in the ability of chitosan to bind fat would likely enhance the probability of chitosan effectively reducing body weight in humans and non-laboratory mammals.
There is great need for a composition that would function synergistically to prevent or limit the bioavailability of fat and cholesterol in order to aid in weight-loss, reduce cholesterol levels and control blood glucose. The present invention is designed to satisfy such a need in the art and is believed to represent a significant advance in improving a person""s health by the rapid elimination of ingested fat and a reduction in the accumulation of harmful cholesterol levels.
The present invention provides a composition to cause weight loss in a warm-blooded animal comprising psyllium and chitosan in a specified ratio, which adsorbs fats in the stomach and intestinal tract thereby limiting absorption of ingested fat. Moreover, the present composition also reduces serum cholesterol.
The present invention further provides a method of dietary supplementation to a warm-blooded animal which comprises administering to the animal effective amounts of a composition comprising psyllium and chitosan, in a proper ratio, and continuing such administration of the composition until body weight reduction occurs.
The present invention contemplates treatment of obesity, hypercholesterolemia and type 2 diabetes. The present composition reduces the absorption of fat calories and cholesterol, thereby promoting weight loss and decreasing serum cholesterol levels. A pharmaceutically acceptable carrier may also be used in the present composition and formulation. The formulation can be manufactured as any form known to the skilled artisan, for example as solid capsules, caplets, soft-gels, liquids, bars, or functional foods.
Other features and advantages of the invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings, which illustrate, by way of example, the features of the invention.